Find the angle there with sectheta=2 exactly over 0

Ammonia molecules have three hydrogen atoms and one nitrogen atom.how many of each atom arein five molecules of ammonia

The floor of a building consists of 3000 tiles which are rhombus shaped and each of it's diagonals are 45 cm and 30 cm in length. find the total cost of polishing the floor, if the cost per m² is rs. 4.

Asoftball team played ten games, scoring 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 runs. they lost by one run in exactly five games. in each of their other games, they scored twice as many runs as their opponent. how many total runs did their opponents score?